The present invention relates to a surgical device that permits the permanent and invisible drainage and/or aeration of chronically or sub-acutely affected maxillary sinuses. The sinus is traditionally drained by means of a drain that exits from the narinary orifice. This allows the treatment for a period of from 7 to 15 days, but not on a permanent basis. It would be therefore desirable to provide a device allowing a permanent drainage of the sinus.